KR102238310B1 - Method for transmitting and receiving packet in transport network - Google Patents

Abstract

A method of transmitting and receiving packets in a transport network is disclosed. A method of operating a controller in a transport network includes: transmitting a request message for requesting a channel status report to at least one transmitting node among a plurality of transmitting nodes included in the transport network, and transmitting a channel status report from the at least one transmitting node. And receiving a response message including state information, and determining a protocol layer used in the at least one transmission node based on the channel state information. Therefore, the performance of the communication network can be improved.

Description

How to send and receive packets in a transport network {METHOD FOR TRANSMITTING AND RECEIVING PACKET IN TRANSPORT NETWORK}

The present invention relates to a technology for transmitting and receiving packets, and more particularly, to a technology for setting a communication path and a protocol layer for transmitting and receiving packets in a transport network.

Mobile packets increased through an existing communication network (for example, a communication network using limited radio resources) due to the increase of mobile subscribers and the spread of smart phones. It may not be easy to deal with. In order to solve this problem, small cell technology or the like may be introduced into a communication network. When small cell technology is introduced into a communication network, mobile packets can be efficiently processed due to a decrease in cell coverage and an increase in the number of cells per unit area.

However, as the number of cells increases, the number of packets transmitted from the core network (or service network) to the cells increases, so a transport network is required to efficiently transmit the increased packets. . In particular, a transport network for efficiently transmitting and receiving packets such as fronthaul, midhaul, and backhaul in a cloud-radio access network (C-RAN) will be required. The transport network may be referred to as “Xhaul transport network” or “crosshaul transport network”.

The transport network can support communication between a base station (or radio unit (RU), remote radio head (RRH), etc.) and a core network (or base band unit (BBU), etc.), and transmits packets to the base station or core network. It may include a plurality of transmitting nodes that transmit. Here, the BBU may be a "BBU pool". Communication between the transmission nodes included in the transport network is performed using wired communication technology (e.g., optical communication technology, Ethernet technology, etc.) or wireless communication technology (e.g., mmWave (millimeter wave) communication technology). Can be done. When a packet is transmitted to a base station or a core network through a plurality of transmission nodes in a transport network, a transmission delay of the packet may occur.

An object of the present invention for solving the above problems is to provide a method of setting a communication path and a protocol layer for transmission and reception of packets in a transport network.

In order to achieve the above object, a method of operating a controller in a transport network according to a first embodiment of the present invention includes requesting a channel status report from at least one of a plurality of transmission nodes included in the transport network. Transmitting a request message, receiving a response message including channel state information from the at least one transmitting node in response to the request message, used by the at least one transmitting node based on the channel state information Determining a protocol layer to be performed, and transmitting a control message including information of the determined protocol layer to the at least one transmission node.

Here, the method of operating the controller further includes receiving a report message including source and destination information of the packet from a first transmission node connected to an access network or a second transmission node connected to a core network among the plurality of transmission nodes. May be included, and the report message may be received before transmission of the request message.

Here, the report message may further include a result of performing DPI on the packet.

Here, the first transmission node may support at least one communication protocol used in the access network and a common communication protocol used in the transport network, and the second transmission node may support at least one communication protocol used in the core network. It can support a communication protocol and the common communication protocol.

Here, the operation method of the controller may further include determining a communication path of the packet based on information included in the report message and the response message, and the communication path may be determined before transmission of the control message. In addition, the control message may further include information on the communication path.

Here, the communication path may be determined based on a transmission speed and a delay time required for transmission of the packet.

Here, when the channel state indicated by the channel state information is greater than or equal to a preset reference, the protocol layer may be determined as a PHY layer.

Here, when the channel state indicated by the channel state information is less than a preset reference, the protocol layer may be determined as a PHY layer, a MAC layer, and an RLC layer.

In order to achieve the above object, a method of operating a transmission node in a transport network according to a second embodiment of the present invention includes the steps of receiving a request message requesting a channel status report from a controller controlling the transport network, and the request Measuring a channel state based on a message, transmitting a response message including measured channel state information to the controller, receiving a control message indicating a protocol layer determined based on the channel state information from the controller And performing communication using the protocol layer indicated by the control message.

Here, the control message may further include information on a communication path determined by the controller, and the protocol layer may be used for communication with another transmission node indicated by the communication path.

Here, when the channel state indicated by the channel state information is greater than or equal to a preset reference, the protocol layer may be determined as a PHY layer, and communication may be performed using the PHY layer.

Here, when the channel state indicated by the channel state information is less than a preset reference, the protocol layer may be determined as a PHY layer, a MAC layer, and an RLC layer, and the PHY layer, the MAC layer, and the RLC layer are used. Communication can be carried out.

In the transport network according to the third embodiment of the present invention for achieving the above object, the controller includes a processor and a memory in which at least one instruction executed by the processor is stored, and the at least one instruction is transmitted to the transport network. A request message for requesting a channel status report is transmitted to at least one transmission node among a plurality of included transmission nodes, and a response message including channel status information from the at least one transmission node is provided in response to the request message. Receiving, determining a protocol layer used in the at least one transmitting node based on the channel state information, and transmitting a control message including information of the determined protocol layer to the at least one transmitting node.

Here, the at least one command may be further executed to receive a report message including source and destination information of the packet from a first transmission node connected to an access network or a second transmission node connected to a core network among the plurality of transmission nodes. In addition, the report message may be received before transmission of the request message.

Here, the report message may further include a result of performing DPI on the packet.

Here, the first transmission node may support at least one communication protocol used in the access network and a common communication protocol used in the transport network, and the second transmission node may support at least one communication protocol used in the core network. It can support a communication protocol and the common communication protocol.

Here, the at least one command may be further executed to determine a communication path of the packet based on information included in the report message and the response message, and the communication path may be determined before transmission of the control message, and the The control message may further include information on the communication path.

Here, the communication path may be determined based on a transmission speed and a delay time required for transmission of the packet.

Here, when the channel state indicated by the channel state information is greater than or equal to a preset reference, the protocol layer may be determined as a PHY layer.

Here, when the channel state indicated by the channel state information is less than a preset reference, the protocol layer may be determined as a PHY layer, a MAC layer, and an RLC layer.

According to the present invention, in a transport network, the state of a transmitting node (for example, resource state, channel state, network state, etc.) and packet characteristics (for example, packet source information, destination information, type and QoS information, etc.) ), a communication path and a protocol layer may be set. A transport node located in a communication path determined in the transport network can transmit and receive packets using the determined protocol layer.

For example, if the channel state (e.g., received signal strength) is greater than or equal to a preset criterion, the protocol layer to be used for communication between the transmitting nodes is a protocol layer (e.g., a physical) layer for which the retransmission procedure is not supported. ) Can be determined. In this case, since only the function of the PHY layer is performed for packet transmission and reception, the transmission delay of the packet in the transport network can be reduced. On the other hand, when the channel state (e.g., received signal strength) is less than a preset criterion, the protocol layer to be used for communication between the transmitting nodes is a protocol layer (e.g., RLC layer, MAC layer, and PHY layer) for which the retransmission procedure is supported. ) Can be determined. In this case, since the functions of the RLC, MAC, and PHY layers are performed for packet transmission and reception, packet transmission can be guaranteed in the transport network. Therefore, packets can be efficiently transmitted and received in the transport network.

Meanwhile, the terminal transmission node of the transport network may support a plurality of communication protocols to perform communication with a base station or a core network supporting different communication protocols. For example, the end transmission node can process a packet received from the base station or the core network using a common communication protocol used in the transport network, and can transmit the processed packet to another transmission node located in the transport network. . In addition, the end transmission node may process a packet received from another transmission node located in the transport network using a communication protocol used in the base station or the core network, and transmit the processed packet to the base station or the core network. That is, in the transport network, the end transmission node can perform a communication protocol conversion function.

Therefore, among the transmission nodes included in the transport network, the transmission nodes other than the terminal transmission node may not support the communication protocol conversion function (i.e., the communication protocol conversion function supported by the terminal transmission node), and the packet transmission/reception function (e.g. For example, it may be set to support a high-speed transmission function). Therefore, a transport network can be efficiently configured because a supported function can be set according to the characteristics of a transport node in the transport network. Consequently, the performance of the transport network can be improved.

1 is a conceptual diagram showing a first embodiment of a communication network.
2 is a block diagram showing a first embodiment of a communication node constituting a communication network.
3 is a conceptual diagram showing a first embodiment of a relay-based communication method in a communication network.
4 is a flow chart showing a first embodiment of a communication method in a communication network.
5 is a block diagram showing a first embodiment of a controller in a communication network.
6 is a conceptual diagram showing a first embodiment of a packet transmission method in a communication network.

In the present invention, various modifications may be made and various embodiments may be provided, and specific embodiments will be illustrated in the drawings and described in detail. However, this is not intended to limit the present invention to a specific embodiment, it should be understood to include all changes, equivalents, and substitutes included in the spirit and scope of the present invention.

Terms such as first and second may be used to describe various elements, but the elements should not be limited by the terms. The above terms are used only for the purpose of distinguishing one component from another component. For example, without departing from the scope of the present invention, a first element may be referred to as a second element, and similarly, a second element may be referred to as a first element. The term and/or includes a combination of a plurality of related listed items or any of a plurality of related listed items.

When a component is referred to as being "connected" or "connected" to another component, it is understood that it may be directly connected or connected to the other component, but other components may exist in the middle. It should be. On the other hand, when a component is referred to as being "directly connected" or "directly connected" to another component, it should be understood that there is no other component in the middle.

The terms used in the present application are only used to describe specific embodiments, and are not intended to limit the present invention. Singular expressions include plural expressions unless the context clearly indicates otherwise. In the present application, terms such as "comprise" or "have" are intended to designate the presence of features, numbers, steps, actions, components, parts, or combinations thereof described in the specification, but one or more other features. It is to be understood that the presence or addition of elements or numbers, steps, actions, components, parts, or combinations thereof does not preclude in advance.

Unless otherwise defined, all terms used herein including technical or scientific terms have the same meaning as commonly understood by one of ordinary skill in the art to which the present invention belongs. Terms as defined in a commonly used dictionary should be interpreted as having a meaning consistent with the meaning in the context of the related technology, and should not be interpreted as an ideal or excessively formal meaning unless explicitly defined in this application. Does not.

Hereinafter, preferred embodiments of the present invention will be described in more detail with reference to the accompanying drawings. In describing the present invention, in order to facilitate an overall understanding, the same reference numerals are used for the same elements in the drawings, and duplicate descriptions for the same elements are omitted.

1 is a conceptual diagram showing a first embodiment of a communication network.

Referring to FIG. 1, the communication network may include an access network, a transport network, and a core network. The access network may include terminals 110-1 to 110-8, base stations 120-1 to 120-6, and the like. The base stations 120-1 to 120-6 may be a radio unit (RU), a remote radio head (RRH), or the like. Terminals 110-1 to 110-8 may be connected to base stations 120-1 to 120-6, and communication between terminals 110-1 to 110-8 and base stations 120-1 to 120-6 Is a 4G communication technology (e.g., a long term evolution (LTE) communication technology specified in 3GPP (3rd generation partnership project), an LTE-A (advanced) communication technology), a 5G communication technology (e.g., mmWave (millimeter wave ) Based communication technology, NR (new radio) communication technology), and the like.

The transport network can support communication between the access network and the core network. For example, the transport network may transmit packets (eg, control packets, data packets) received from the access network to the core network, and may transmit packets received from the core network to the access network. The transport network may be referred to as “Xhaul transport network” or “crosshaul transport network”.

The transport network may include a plurality of transmission nodes 130-1 to 130-12. Communication between the transmission nodes 130-1 to 130-12 is performed using wired communication technology (eg, optical communication technology, Ethernet technology, etc.) or wireless communication technology (eg, mmWave communication technology). Can be. For example, communication between transmission nodes #1 to #6 (130-1 to 130-6) may be performed using wireless communication technology, and transmission nodes #7 to #12 (130-7 to 130-12) Communication between the two can be performed using wired communication technology.

The operation of the plurality of transmission nodes 130-1 to 130-12 included in the transport network (eg, packet transmission/reception operation) may be controlled by the controller 140. The controller 140 may be included in the transport network. Alternatively, the controller 140 may be configured separately from the transport network. An end transmission node among the plurality of transmission nodes 130-1 to 130-12 may be connected to an access network, a core network, a controller 140, and the like. For example, the transmission node #1 (130-1) may be connected to the core network, the controller 140, and the like, and each of the transmission nodes #4 to #6 (130-4 to 130-6) is the base station #1 to #3 It can be connected to (120-1 to 120-3). Transmission node #7 (130-7) may be connected to the core network, the controller 140, etc., and each of the transmission nodes #10 to #12 (130-10 to 130-12) is the base station #4 to #6 (120-4). To 120-6).

The controller 140 may be connected to the transport network and may control the operation of the plurality of transmission nodes 130-1 to 130-12 included in the transport network. The controller 140 may be referred to as "X-Hall controller" or "Cross-Hall controller", and may support software defined network (SDN) technology. For example, the controller 140 may perform an operation of setting a communication path and a control operation for transmitting/receiving packets in a transport network using an SDN-based flow control protocol.

The core network may be connected to the transport network and communicate with the access network through the transport network. When the core network is an evolved packet core (EPC) network, the core node 150 included in the core network is a mobility management entity (MME), a serving-gateway (S-GW), and a packet data network (PDN) (P-GW). -gateway), etc. When the core network supports a cloud-radio access network (C-RAN), the core node 150 may be a base band unit (BBU) or the like. The BBU may indicate "BBU pool".

Meanwhile, a communication node included in the communication network shown in FIG. 1 may be configured as follows.

2 is a block diagram showing a first embodiment of a communication node constituting a communication network.

Referring to FIG. 2, the communication node 200 includes terminals 110-1 to 110-8, base stations 120-1 to 120-6, and transmission nodes 130-1 to 130-12 shown in FIG. , The controller 140, the core node 150, and the like. The communication node 200 may include at least one processor 210, a memory 220, and a transmission/reception device 230 connected to a network to perform communication. In addition, the communication node 200 may further include an input interface device 240, an output interface device 250, and a storage device 260. Each of the components included in the communication node 200 may be connected by a bus 270 to communicate with each other.

The processor 210 may execute a program command stored in at least one of the memory 220 and the storage device 260. The processor 210 may mean a central processing unit (CPU), a graphics processing unit (GPU), or a dedicated processor in which methods according to embodiments of the present invention are performed. Each of the memory 220 and the storage device 260 may be configured with at least one of a volatile storage medium and a nonvolatile storage medium. For example, the memory 220 may be composed of at least one of read only memory (ROM) and random access memory (RAM).

Next, a method of operating a communication node included in a communication network will be described. Even when a method performed in the first communication node (for example, transmission or reception of a signal) among communication nodes is described, the second communication node corresponding thereto is a method corresponding to the method performed in the first communication node (for example, For example, signal reception or transmission) can be performed. That is, when the operation of the terminal is described, the corresponding base station may perform the operation corresponding to the operation of the terminal. Conversely, when the operation of the base station is described, a terminal corresponding thereto may perform an operation corresponding to the operation of the base station.

Meanwhile, communication may be performed based on a relay technology in a communication network.

3 is a conceptual diagram showing a first embodiment of a relay-based communication method in a communication network.

Referring to FIG. 3, the communication network may include a terminal 310, a base station #1 320-1, a base station #2 320-2, an EPC 350, and the like. The terminal 310 may be the same as or similar to the terminals 110-1 to 110-8 in the communication network of FIG. 1, and a protocol layer (eg, a user plane) of the terminal 310 ) Is an application layer, a transmission control protocol (TCP) layer, an internet protocol (IP) layer, a packet data convergence protocol (PDCP) layer, a radio link control (RLC) layer, and a medium access control (MAC) layer. It may include a layer, a physical (PHY) layer, and the like.

Base station #1 (320-1) may be the same or similar to the base stations (120-1 to 120-6) in the communication network of Figure 1, the protocol layer of the base station #1 (320-1) (for example, user The protocol layer of the plane) may include a PDCP layer, an RLC layer, a MAC layer, a PHY layer, and the like. The base station #2 320-2 may be the same as or similar to the base stations 120-1 to 120-6 or the transmission nodes 130-1 to 130-12 in the communication network of FIG. 1. The protocol layer (e.g., the protocol layer of the user plane) of the base station #2 320-2 is a PDCP layer, an RLC layer, a MAC layer, a PHY layer, and a general packet radio service (GTP-U) tunneling protocol-user. plane) layer, user datagram protocol (UDP) layer, IP layer, L2, L1, and the like. The EPC 350 may be the same or similar to the core node 150 in the communication network of FIG. 1, and the protocol layer (eg, the protocol layer of the user plane) of the EPC 350 is an application layer, a TCP layer, and an IP Layer, GTP-U layer, UDP layer, L2, L1, etc. may be included.

An access link may be established between the terminal 310 and the base station #1 320-1, and communication between the terminal 310 and the base station #1 320-1 may be performed using an access link. . A self-backhaul link may be established between base station #1 (320-1) and base station #2 (320-2), and base station #1 (320-1) and base station #2 (320-2) Communication between the two can be performed using a self-backhaul link. The self-backhaul link may be a link included in the transport network in the communication network of FIG. 1. Here, base station #1 320-1 may be a relay base station, and base station #2 320-2 may be an anchor base station. A backhaul link may be established between the base station #2 320-2 and the EPC 350, and communication between the base station #2 320-2 and the EPC 350 may be performed using a backhaul link.

A packet transmitted from the terminal 310 to the EPC 350 (or a packet transmitted from the EPC 350 to the terminal 310) is a PHY layer (e.g. For example, not only the function of L1), but also of the upper layer of the PHY layer (e.g., L1) (e.g., MAC layer, RLC layer, PDCP layer, L2, IP layer, UDP layer, GTP-U layer, etc.) After the function is performed, it may be transmitted to the EPC 350 (or the terminal 310).

When the requested delay time for packet transmission is 20ms (millisecond), not only the function of the PHY layer (eg, L1) but also of the PHY layer (eg, L1) When the function of the upper layer (eg, MAC layer, RLC layer, PDCP layer, L2, IP layer, UDP layer, GTP-U layer, etc.) is performed, packet transmission may not satisfy the required delay time. .

To solve this problem, packets are sent to the EPC 350 (or the terminal 310) after only the function of the PHY layer (eg, L1) is performed in the base stations 320-1 and 320-2. When transmitted, the packet may not be received by the EPC 350 (or the terminal 310) depending on the state of the link (eg, an access link, a self-backhaul link, a backhaul link). Communication methods for solving this problem will be described below.

4 is a flow chart showing a first embodiment of a communication method in a communication network.

4, the communication network is terminal #1 (110-1), base station #1 (120-1), transmission node #1 (130-1), transmission node #2 (130-2), transmission node # 4 (130-4), may include a controller 140, and the like. Terminal #1 (110-1), base station #1 (120-1), transmission node #1 (130-1), transmission node #2 (130-2), transmission node #4 (130-4) and controller ( 140) Each is terminal #1 (110-1), base station #1 (120-1), transmission node #1 (130-1), transmission node #2 (130-2), and transmission node # shown in FIG. It may be 4 (130-4) and the controller 140, and may be configured in the same or similar to the communication node 200 shown in FIG.

The access network may include terminal #1 110-1, base station #1 120-1, and the like. Terminal #1 110-1 may be connected to base station #1 120-1, and base station #1 120-1 may be a radio unit (RU), a radio remote head (RRH), or the like. The transport network may include transmission node #1 (130-1), transmission node #2 (130-2), transmission node #4 (130-4), and the like. Communication between the transmission nodes 130-1, 130-2, and 130-4 may be performed based on a wireless communication technology (eg, mmWave communication technology). Transmission node #1 (130-1) and transmission node #4 (130-4) may be terminal transmission nodes in the transport network. The terminal transmission node (eg, transmission node #1 (130-1)) connected to the controller 140 and the core node 150 may be referred to as a gateway (or an X-Hall gateway).

The transmission node #1 (130-1) may be connected to the controller 140 and the core node 150, and to perform communication with the controller 140 and the core node 150 using different communication protocols. Can support communication protocols. In addition, the transmission node #1 (130-1) may support a common communication protocol used in the transport network. Transmission node #1 (130-1) can process the packet received from the controller 140 or the core node 150 using a common communication protocol used in the transport network, and transfer the processed packet to the transport network. It can transmit to other transport nodes located.

In addition, transmission node #4 (130-4) may be connected to base station #1 (120-1), and a plurality of communication protocols to perform communication with base station #1 (120-1) using different communication protocols. Can support them. In addition, transmission node #4 (130-4) may support a common communication protocol used in the transport network. Transmission node #4 (130-4) can process the packet received from base station #1 (120-1) using a common communication protocol used in the transport network, and can process the processed packet to another location located in the transport network. It can be transmitted to the transmitting node.

That is, among the transport nodes included in the transport network, a transport node (for example, except for a terminal transport node (for example, transport node #1 (130-1), transport node #4 (130-4), etc.)) Transmission node #2 (130-2), etc.) may be configured to support only a packet transmission/reception function (eg, a high-speed transmission function), and the end transmission node is not supported by a transmission node that supports only the packet transmission/reception function. It can support functions that do not. Therefore, a transport network can be efficiently configured because a supported function can be set according to the characteristics of a transport node in the transport network.

The core node 150 may be an MME, S-GW, P-GW, BBU (or BBU pool), or the like. The controller 140 may perform a function of a radio resource control (RRC) layer, and may control communication of the transmission nodes 130-1, 130-2, and 130-4 included in the transport network. The controller 140 may be configured as follows.

5 is a block diagram showing a first embodiment of a controller in a communication network.

Referring to FIG. 5, the controller 140 may include a transmission node control unit 141 and a path control unit 144. The transmission node control unit 141 and the path control unit 144 may be the processor 200 shown in FIG. 2. The transmission node control unit 141 may include a decision application 142 and a plurality of control APPs 143-1, 143-2, .., 143-12. For example, each of the plurality of control APPs 143-1, 143-2, .., 143-12 is the transmission nodes 130-1, 130-2, .., 130- in the communication network of FIG. 12) can be mapped.

In this case, the controller 140 uses a plurality of control APPs 143-1, 143-2, .., 143-12 to transmit nodes 130-1, 130-2, .., 130-12. ) Can be controlled. For example, the controller 140 transmits nodes 130-1, 130-2, .., 130-12 through a plurality of control APPs 143-1, 143-2, .., 143-12). ) Channel state information may be obtained, and the channel state information may be transmitted to the decision APP 142. The decision APP 142 may determine a communication path of a packet based on channel state information, packet analysis information received from an end transmission node, and the like, and may determine a protocol layer used in a transmission node located in the determined communication path. The transmission node controller 141 may inform the path controller 144 of the determined communication path and protocol layer.

The path control unit 144 may include an SDN control unit 145. That is, the path controller 144 may support SDN technology. The path control unit 144 may obtain information on the communication path and the protocol layer from the transmission node control unit 141, and transmit information on the communication path and the protocol layer to transmission nodes (for example, a transmission node located in the communication path). S), and control communication of transport nodes based on information on a communication path and a protocol layer.

Referring back to FIG. 4, the transmission node #1 130-1 may receive a packet (eg, a control packet, a data packet) from the core node 150. The packet may be transmitted from the core node 150 to the transmission node # 1 130-1 through a GTP-U tunnel established between the transmission node # 130-1 and the core node 150. Transmission node #1 (130-1) may perform analysis on the received packet (S400). For example, the transmission node #1 130-1 may analyze a packet using a deep packet inspection (DPI) technology. By performing analysis on the packet, the transmission node #1 (130-1) transmits the packet's source information (i.e., source address), destination information (i.e., destination address), and type (e.g., control packet, data packet). , Quality of service (QoS) information, etc. may be obtained. Here, the source information may indicate the core node 150 or another communication node (eg, a terminal), and the destination information may indicate the terminal #1 110-1. Qos information includes QCI (QoS class identifier), ARP (allocation and retention priority), required transmission rate (e.g., GBR (guaranteed bit rate), MBR (maximum bit rate)), and required delay time (e. , Packet delay budget (PDB)), and the like.

Transmission node #1 (130-1) may generate a report message including analysis information of the packet (eg, source information, destination information, type, QoS information, etc.), and the generated report message May be transmitted to the controller 140 (S401). The controller 140 (for example, the transmission node control unit 141 or the path control unit 144) may receive a report message from the transmission node #1 130-1, and packet analysis information from the received report message You can check. For example, the controller 140 may determine that there is a packet to be transmitted from the transmission node #1 130-1 to the terminal #1 110-1 based on the report message, and the terminal #1 110 -1) You can check the type of packet to be transmitted, QoS information, etc.

The controller 140 is a transport node belonging to a transport network (eg, a transport network to which the transport node #1 (130-1) belongs, a transport network connected to an access network to which the terminal #1 (110-1) belongs). The request message can be transmitted to the field (S402). The request message may be transmitted through the control APP of the controller 140. For example, the request message is transmitted through the control APP#1 (143-1), the control APP#2 (143-2) and the control APP #12 (143-12) through each of the transmission node #1 (130-1), It may be transmitted to node #2 (130-2) and transmission node #12 (130-12). The request message may instruct to report a channel state between communication nodes, a resource state (eg, available resource) of a communication node, a network state, and the like. In FIG. 4, the request message is shown to be transmitted to transmission node #1 (130-1), transmission node #2 (130-2), and transmission node #4 (130-4), but the request message is broadcast in the transport network. It can be transmitted in a casting method.

Alternatively, the controller 140 (eg, the determination APP 142 of the controller 140) may determine a communication path (eg, a candidate communication path) for packet transmission based on the information included in the report message. In addition, it is possible to transmit a request message to transmission nodes located in the communication path. For example, the communication path (for example, the candidate communication path) is the communication path of "transmission node #4 (130-4)-transmission node #2 (130-2)-transmission node #1 (130-1)" When it is determined as, the controller 140 may transmit a request message to the transmission node #1 130-1, the transmission node #2 130-2, and the transmission node #4 130-4.

When the request message is received from the controller 140, each of the transmission nodes included in the transport network may measure a channel state with a neighboring transmission node (S403). For example, each of the transmission node #2 (130-2) and the transmission node #4 (130-4) is the channel state between the transmission node #2 (130-2) and the transmission node #4 (130-4) (for example, For example, the received signal strength) can be measured, and each of the transmission node #1 (130-1) and the transmission node #2 (130-2) is the transmission node #1 (130-1) and the transmission node #2 (130- 2) It is possible to measure the inter-channel state (eg, the strength of the received signal). Transmitting nodes receiving the request message may generate a response message including channel status information (eg, received signal strength), resource status information (eg, available resource information), network status information, and the like, The generated response message may be transmitted to the controller 140 (S404). In FIG. 4, steps S403 and S404 are shown to be performed in transmission node #1 (130-1), transmission node #2 (130-2), and transmission node #4 (130-4), but steps S403 and S404 May be performed in the transmitting nodes that have received the request message.

The controller 140 may receive response messages from transmitting nodes. The response message may be received through the control APP of the controller 140. For example, the response message is transmitted through the control APP#1 (143-1), the control APP#2 (143-2) and the control APP #12 (143-12) through each of the transmission node #1 (130-1), It may be received from node #2 (130-2) and transmission node #12 (130-12).

If the communication path of the packet is not determined before step S402, the controller 140 (for example, the decision APP 142 of the controller 140) is based on information included in the report message, information included in the response message, etc. Thus, the communication path of the packet can be determined. For example, the controller 140 may determine the communication path of the packet in consideration of the source information, destination information, type and QoS information of the packet, as well as channel state information and resource state information of a transmitting node.

When the communication path of the packet is determined as the communication path of "transmission node #4 (130-4)-transmission node #2 (130-2)-transmission node #1 (130-1)", the controller 140 (for example, For example, the decision APP 142 of the controller 140 is used by the transmission node #1 (130-1), the transmission node #2 (130-2), and the transmission node #4 (130-4) belonging to the determined communication path. It is possible to determine the protocol layer (S405). The protocol layer may be determined based on channel state information included in the response message. For example, when the channel state information (eg, received signal strength) is greater than or equal to a preset threshold, the controller 140 converts the protocol layer used for packet transmission to a protocol layer that does not support the retransmission procedure (for example, , PHY layer). On the other hand, when the channel state information (eg, received signal strength) is less than a preset threshold, the controller 140 transfers the protocol layer used for packet transmission to a protocol layer (eg, a PHY layer) supporting the retransmission , MAC layer and RLC layer). When the communication path and the protocol layer are determined by the transmission node controller 141, the determined communication path and protocol layer information may be transmitted from the transmission node controller 141 to the path controller 144.

In the description below, the communication path of the packet is determined as the communication path of "transmission node #4 (130-4)-transmission node #2 (130-2)-transmission node #1 (130-1)", and transmission node #1 The protocol layer used for communication between (130-1) and transmission node #2 (130-2) is determined as the PHY layer, and between transmission node #2 (130-2) and transmission node #4 (130-4) It is assumed that the protocol layer used for communication is determined as a PHY layer, a MAC layer, and an RLC layer.

The controller 140 (for example, the path control unit 144 of the controller 140 or the SDN control unit 145) includes information on the communication path (eg, a flow table for packet transmission/reception) and a protocol layer. A control message including information can be generated, and the control message can be transmitted to transmission nodes located in the communication node (e.g., transmission node #1 (130-1), transmission node #2 (130-2), and transmission node #). 4 (130-4)) can be transmitted (S406).

In the control message transmitted to the transmission node #1 (130-1), the information of the communication path is "transmission node #4 (130-4)-transmission node #2 (130-2)-transmission node #1 (130-1) )" can indicate a communication path, and the information of the protocol layer can indicate the PHY layer. In the control message transmitted to the transmission node #2 (130-2), the information of the communication path is "transmission node #4 (130-4)-transmission node #2 (130-2)-transmission node #1 (130-1) )", and the information of the protocol layer for communication between the transmission node #2 (130-2) and the transmission node #1 (130-1) may indicate the PHY layer, and the transmission node # The information of the protocol layer for communication between the 2 (130-2) and the transmission node #4 (130-4) may indicate the PHY layer, the MAC layer, and the RLC layer. In the control message transmitted to the transmission node #4 (130-4), the information of the communication path is "transmission node #4 (130-4)-transmission node #2 (130-2)-transmission node #1 (130-1) )", and the information of the protocol layer may indicate the PHY layer, the MAC layer, and the RLC layer.

When a control message is received from the controller 140, each of the transmission node #1 (130-1), the transmission node #2 (130-2), and the transmission node #4 (130-4) is a communication path based on the control message. And it is possible to check the protocol layer, it is possible to set the protocol layer indicated by the control message (S407). For example, the transmission node #1 (130-1) may set the PHY layer for communication between the transmission node #1 (130-1) and the transmission node #2 (130-2). The transmission node #2 (130-2) may set the PHY layer for communication between the transmission node #1 (130-1) and the transmission node #2 (130-2), and the transmission node #2 (130-2) and For communication between transmission node #4 (130-4), a PHY layer, a MAC layer, and an RLC layer may be set. The transmission node #4 (130-4) may set the PHY layer, the MAC layer, and the RLC layer for communication between the transmission node #2 (130-2) and the transmission node #4 (130-4). "Terminal #1 (110-1)-Base station #1 (120-1)-Transmission node #4 (130-4)-Transmission node #2 (130-2)-Transmission node #1 (130-1)" Packet transmission in the communication path can be performed as follows.

6 is a conceptual diagram showing a first embodiment of a packet transmission method in a communication network.

6, the communication network is terminal #1 (110-1), base station #1 (120-1), transmission node #1 (130-1), transmission node #2 (130-2), transmission node # 4(130-4), and the like. Terminal #1 (110-1), base station #1 (120-1), transmission node #1 (130-1), transmission node #2 (130-2), and transmission node #4 (130-4) are each shown in FIG. Terminal #1 (110-1), base station #1 (120-1), transmission node #1 (130-1), transmission node #2 (130-2), and transmission node #4 (130-4) shown in FIG. Can be the same as ).

Since the communication between the transmission node #1 (130-1) and the transmission node #2 (130-2) is performed through the PHY layer, the transmission node #1 (130-1) is a function of the PHY layer (e.g., coding ( coding), modulation, resource mapping, etc.), the packet received from the core node 150 can be processed, and the packet in which the function of the PHY layer is performed is transmitted to the transmission node #2 (130- 2) can be transmitted (S408). Transmission node #2 (130-2) can receive a packet from the transmission node #1 (130-1), the function of the PHY layer (e.g., decoding (decoding), demodulation (demodulation), resource demapping ( resource demapping), etc.) to process the received packet. Since only the function of the PHY layer can be performed in communication between the transmission node #1 130-1 and the transmission node #2 130-2, the transmission delay of the packet can be reduced.

Since the communication between the transmission node #2 (130-2) and the transmission node #4 (130-4) is performed through the PHY layer, the MAC layer, and the RLC layer, the transmission node #1 (130-1) is the function of the RLC layer ( For example, AM (acknowledged mode) function, etc.), MAC layer functions (e.g., HARQ (hybrid automatic repeat request) function, scheduling function, etc.) and PHY layer functions (e.g., coding, By performing modulation, resource mapping, etc.), the packet received from the transmission node #1 (130-1) can be processed, and the packet in which the functions of the RLC layer, MAC layer, and PHY layer are performed is transmitted to the transmission node #4 (130-). 4) can be transmitted (S409).

Transmission node #4 (130-4) can receive a packet from the transmission node #2 (130-2), the function of the PHY layer (for example, decoding, demodulation, resource demapping, etc.), the function of the MAC layer A received packet may be processed by performing (eg, HARQ function, scheduling function, etc.) and RLC layer functions (eg, AM function, etc.). For example, if a packet is not successfully received from the transmission node #2 (130-2), the transmission node #4 (130-4) uses the function of the RLC layer or the MAC layer to retransmit the packet to the transmission node# You can make a request to 2(130-2). When a request for retransmission of a packet is received from the transmission node #4 130-4, the transmission node #2 130-2 may retransmit the packet to the transmission node #4 130-4. Since a packet retransmission procedure may be performed in communication between the transmission node #2 130-2 and the transmission node #4 130-4, transmission of the packet may be guaranteed.

Transmission node #4 (130-4) is a protocol layer used for communication between transmission node #4 (130-4) and base station #1 (120-1) (e.g., PDCP layer, RLC layer, MAC layer, PHY layer) can process the packet received from the transmission node #2 (130-2) by performing the functions, and can transmit the processed packet to the base station #1 (120-1) (S410). Base station #1 (120-1) can receive packets from transmission node #4 (130-4), and is used for communication between base station #1 (120-1) and transmission node #4 (130-4). The received packet can be processed by performing the functions of the protocol layer (eg, the PDCP layer, the RLC layer, the MAC layer, and the PHY layer). In addition, base station #1 (120-1) is a protocol layer used for communication between base station #1 (120-1) and terminal #1 (110-1) (e.g., PDCP layer, RLC layer, MAC layer, PHY layer) can process the packet received from the transmission node #4 (130-4), and can transmit the processed packet to the terminal #1 (110-1) (S411). Terminal #1 (110-1) can receive a packet from base station #1 (120-1), and can process the received packet by performing the functions of the protocol layer supported by terminal #1 (110-1). I can.

The methods according to the present invention may be implemented in the form of program instructions that can be executed through various computer means and recorded in a computer-readable medium. The computer-readable medium may include program instructions, data files, data structures, and the like alone or in combination. The program instructions recorded on the computer-readable medium may be specially designed and configured for the present invention, or may be known and usable to those skilled in computer software.

Examples of computer-readable media include hardware devices specially configured to store and execute program instructions, such as rom, ram, flash memory, and the like. Examples of program instructions include machine language codes such as those produced by a compiler, as well as high-level language codes that can be executed by a computer using an interpreter or the like. The above-described hardware device may be configured to operate as at least one software module to perform the operation of the present invention, and vice versa.

Although described with reference to the above embodiments, those skilled in the art will understand that various modifications and changes can be made to the present invention without departing from the spirit and scope of the present invention described in the following claims. I will be able to.

Claims (20)

As a method of operating a controller in a transport network supporting communication between an access network and a core network,
Transmitting a request message for requesting a channel status report to at least one transmission node among a plurality of transmission nodes included in the transport network;
Receiving a response message including channel state information from the at least one transmitting node in response to the request message;
Determining a protocol layer used in the at least one transmission node based on the channel state information; And
And transmitting a control message including information of the determined protocol layer to the at least one transmission node. The method according to claim 1,
The operation method of the controller,
Receiving a report message including source and destination information of a packet from a first transmission node connected to the access network or a second transmission node connected to the core network among the plurality of transmission nodes, The report message is received before transmission of the request message. The method according to claim 2,
The report message further includes a result of performing deep packet inspection (DPI) on the packet. The method according to claim 2,
The first transmission node supports at least one communication protocol used in the access network and a common communication protocol used in the transport network, and the second transmission node supports at least one communication protocol used in the core network and Supporting the common communication protocol, a method of operation of a controller. The method according to claim 2,
The operation method of the controller,
Determining a communication path of the packet based on information included in the report message and the response message, wherein the communication path is determined before transmission of the control message, and the control message is information on the communication path. Further comprising, the method of operation of the controller. The method of claim 5,
The communication path is determined based on a transmission rate and a delay time required for transmission of the packet. The method according to claim 1,
When the channel state indicated by the channel state information is greater than or equal to a preset reference, the protocol layer is determined as a physical (PHY) layer. The method according to claim 1,
When the channel state indicated by the channel state information is less than a preset reference, the protocol layer is determined as a PHY layer, a medium access control (MAC) layer, and a radio link control (RLC) layer. As a method of operating a transmission node in a transport network supporting communication between an access network and a core network,
Receiving a request message requesting a channel status report from a controller controlling the transport network;
Measuring a channel state based on the request message;
Transmitting a response message including the measured channel state information to the controller;
Receiving a control message indicating a protocol layer determined based on the channel state information from the controller; And
And performing communication using the protocol layer indicated by the control message. The method of claim 9,
The control message further includes information of a communication path determined by the controller, and the protocol layer is used for communication with another transmission node indicated by the communication path. The method of claim 9,
When the channel state indicated by the channel state information is greater than or equal to a preset reference, the protocol layer is determined as a physical (PHY) layer, and communication is performed using the PHY layer. The method of claim 9,
When the channel state indicated by the channel state information is less than a preset reference, the protocol layer is determined as a PHY layer, a medium access control (MAC) layer, and a radio link control (RLC) layer, and the PHY layer, the MAC layer And communication is performed using the RLC layer. As a controller in a transport network supporting communication between an access network and a core network,
Processor; And
Includes a memory (memory) in which at least one instruction executed in the processor is stored,
The at least one command,
Transmitting a request message for requesting a channel status report to at least one transmission node among a plurality of transmission nodes included in the transport network;
In response to the request message, receiving a response message including channel state information from the at least one transmitting node;
Determining a protocol layer used in the at least one transmission node based on the channel state information; And
A controller executed to transmit a control message including information of the determined protocol layer to the at least one transmitting node. The method of claim 13,
The at least one command,
Further executed to receive a report message including source and destination information of a packet from a first transmission node connected to the access network or a second transmission node connected to the core network among the plurality of transmission nodes, and the report A message is received prior to transmission of the request message. The method of claim 14,
The report message further includes a result of performing deep packet inspection (DPI) for the packet. The method of claim 14,
The first transmission node supports at least one communication protocol used in the access network and a common communication protocol used in the transport network, and the second transmission node supports at least one communication protocol used in the core network and A controller that supports the common communication protocol. The method of claim 14,
The at least one command,
It is further executed to determine a communication path of the packet based on information included in the report message and the response message, the communication path is determined before transmission of the control message, and the control message further includes information on the communication path. Including, the controller. The method of claim 17,
The communication path is determined based on a transmission rate and a delay time required for transmission of the packet. The method of claim 13,
When a channel state indicated by the channel state information is equal to or greater than a preset reference, the protocol layer is determined as a physical (PHY) layer. The method of claim 13,
When the channel state indicated by the channel state information is less than a preset reference, the protocol layer is determined as a PHY layer, a medium access control (MAC) layer, and a radio link control (RLC) layer.

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